Cryptanalysis Workshop Session 1

10:00 ΓÇô 11:00 AM Title: Unaligned Rebound Attack for KECCAK Speaker: Thomas Peyrin Affiliation: Nanyang Technological University, Singapore Abstract: In this talk, we analyze the internal permutations of KECCAK, one of the NIST SHA-3 competition finalists, in regard to differential properties. By carefully studying the elements composing those permutations, we are able to derive most of the best known differential paths for up to 5 rounds. We then use these unaligned differential paths and adapt the rebound attack in order to derive distinguishers for up to 8 rounds of the internal permutations of the submitted version of KECCAK. Our results have been implemented and verified experimentally on a small version of KECCAK and this is currently the best known differential attack against KECCAK. 11:00 AM ΓÇô 12:00 PM Title: Toward Extending Integral Based Known-Key Distinguisher on AES Speaker: Yu Sasaki Affiliation: NTT Corporation, Japan Abstract: We revisit the integral based known-key distinguisher on AES. First, we give a summary of two papers; the original distinguisher by Knudsen and Rijmen at Asiacrypt 2007 and its formalization called middletext distinguisher proposed by Minier et al. at Africacrypt 2009. We then point out that, with following the formalization by Minier et al., the previous integral known-key distinguisher can be extended to a 10-round middletext distinguisher.